Debt Instrument, Proceeds To Be Paid To Lender, Percent

No definition available.

Name:	efoi_DebtInstrumentProceedsToBePaidToLenderPercent
Namespace Prefix:	efoi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentUnamortizedPremium
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=efoi_IliadNotePurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Iliad Note (Details) - USD ($)			1 Months Ended		12 Months Ended
Debt - Iliad Note (Details) - USD ($)	Dec. 01, 2020	Nov. 25, 2019	Apr. 30, 2021	Jan. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Proceeds from issuance			$ 1,500,000
Percent proceeds to be paid to Lender				10.00%
Payments on the Iliad Note					$ 0	$ 1,306,000
Iliad Note
Debt Instrument [Line Items]
Principal amount		$ 1,300,000
Original issue discount		142,000
Proceeds from issuance		1,100,000
Debt issuance costs		$ 15,000
Repayments of debt	$ 30,000
Write off of remaining related debt and acquisition cost	$ 117,000
Stated interest rate		8.00%